Field
The disclosed concept pertains generally to charging stations and, more particularly, to charging stations for electric vehicles (EVs). The disclosed concept further pertains to connectors for charging stations. The disclosed concept further pertains to methods of charging EVs with a charging station.
Background Information
With the development of electric vehicle technology, the number of EVs is growing rapidly, and electric vehicle charging stations, similar to gas stations, have become popular. An EV charging station, also called an electric recharging point, charging point, and EVSE (Electric Vehicle Supply Equipment), is an element in an infrastructure that supplies electric energy for the recharging of electric vehicles, plug-in hybrid electric-gasoline vehicles, or semi-static and mobile electrical units such as exhibition stands. An EV charging station is a device that safely allows electricity to flow. These charging stations and the protocols established to create them are known as EVSE, and they enhance safety by enabling two-way communication between the charging station and the electric vehicle.
The 1996 NEC and California Article 625 define EVSE as being the conductors, including the ungrounded, grounded, and equipment grounding conductors, the electric vehicle connectors, attachment plugs, and all other fittings, devices, power outlets or apparatus installed specifically for the purpose of delivering energy from premises wiring to an electric vehicle. EVSE is defined by the Society of Automotive Engineers (SAE) recommended practice J1772 and the National Fire Protection Association (NFPA) National Electric Code (NEC) Article 625. While the NEC defines several safety requirements, J1772 defines the physical conductive connection type, five pin functions (i.e., two power pins (Hot1 and Hot2 or neutral; or Line 1 and Line 2), one ground pin, one control pilot pin, and one proximity pin), the EVSE to EV handshake over the pilot pin, and how both parts (EVSE and EV) are supposed to function. Two-way communication seeks to ensure that the current passed to the EV is both below the limits of the EV charging station itself and below the limits of what the EV can receive. There are additional safety features, such as a safety lock-out, that does not allow current to flow from the EV charging station until the EV connector or EV plug is physically inserted into the EV and the EV is ready to accept energy. For example, J1772 in North America uses a very simple but effective pilot circuit and handshake in the EVSE.
EV charging stations consist generally of a completely separate and unique box along with a connected EV cable/connector for the intended purpose of charging the EV. In known EV charging stations, charging status is provided on the charging box, which commonly includes a number of indicators for power and state. However, it is desirable to have additional indicators of charging status on the EV charging station.
There is, therefore, room for improvement in charging stations and in connectors therefor.
There is also room for improvement in methods of charging an EV with a charging station.